Telephone-circuit



('No Model.)

w. W, JACQUES. TELEPHONE CIRCUIT.

No. 453,483. Patented June 2, 1891.

77 sss. v fizv/enior.

me mums versus ca, PHo'ro-u'rnu, wusummun, u c

UNITED STATES PATENT OFFICE.

VILLIAM W. JACQUES, OF NEWTON, ASSIGNOR TO THE AMERICAN BELL TELEPHONECOMPANY, OF

BOSTON, MASSACHUSETTS.

TELEPHONE-CIRCUIT.

SPECIFICATION forming part of Letters Patent No. 453,483, dated June 2,1891.

Application filed March '7, 1891- To all whom it may concern.-

Be it known that I, WILLIAM W. JACQUES, of Newton, in the State ofMassachusetts, have invented a new and useful Improvement inTelephone-Circuits, of-which the following is a specification.

The object of the invention is with a given number of metallic circuitsto increase such number without adding to the number of wires andWithout changing the electrical conditions of the original circuits. Asin other systems, original metallic circuits are used in additional orimposed circuits as single conductors- 5. e., as one wire, either theoutgoing or the return wires of a metallic circuit; but whereas in othersystems this has been done always to the detriment of the originalcircuits, and whereas the additional or imposed circuits have been inevery case inferior to the original circuits of which they have beencomposed, in my system each original circuit is unimpaired and works asif there were no additional circuit or circuits imposed upon it, andeach imposed circuit is superior to the original circuits of which itmakesuse. In the old systems sometimes considerable resistances havebeen interposed directly in the main or original circuits, as whereinductioncoils have been used with conductors of the original circuitsfor the purpose of inducing upon them the currentof an additionalcircuit, and in such cases the additional circuit has had in it twice asmany coils as the original. At other times a part of the current of anoriginal circuit has been shunted off, as where the instruments inoriginal circuits have been placed in bridges with resistances behindthem, and in this latter case the additional circuit has contained allthese resist ances. Moreover, where the number of metallic circuits isincreased by the use of bridges or induction-coils it is exceedinglydifficult to maintain the proper proportion of the resistances of thebridges or the proper balance of the induction-coils among themselves,as the case may be.

In carrying out my invention I dispense with bridges and induction-coilsand employ condensers as a means for inducing the currents of theadditional circuits upon the original lines in such manner that theelectrical Serial No. 384,104. (No model.)

condition of the original line is not changed. The original lines arenot cut, and nothing in the nature of a resistance is introduced inthem. It is only necessary that the two condensers inserted in the twobranches of any one metallic circuit, as hereinafter described, shallhave the same inductive capacity, and from this it follows, as willhereinafter appear, that the invention is as applicable to an odd numberof original circuits as to an even number. r

In the dra\vings,Figure l is a diagram rep resenting an additionalmetallic circuit imposed upon two original metallic circuits accordingto myinvention. Fig. 2 is a diagram disclosing the same invention thatis shown in Fig. 1, but more fully illustrative of apparatus actuallyemployed in practicing the invention. Fig. 3 is a diagram illustratingthe manner in which two additional metallic circuits may be imposed uponfour original metallic circuits, one additional circuit upon each pairof original circuits, and also how a third additional circuit may beimposed upon the first two additional circuits. Fig. 4 is a diagramrepresentingadditional metallic circuits imposed upon an odd number oforiginal metallic circuits according to my inven tion.

In Fig. 1 the wires 1 and 2 form, as shown, an original metallic circuitA, and T T are telephones at either end. In like manner the wires 3 and4 form asecond metallic circuit A and T T are telephones at either end.

C C are condensers connected with wire 1 of the original circuit A ateither end, and C C are condensers correspondingly connected with wire 2of the same circuit at either end. One plate of each condenser C C ateither end of the circuit is directly connected with its line-wire, asshown, while the opposite plates are connected in loop Z, as shown. Inlike manner condensers C and C are connected with wires 3 and 4 of thesecond metallic circuit A at either end thereof, one plate of each pairof condensers being in di rect contact with its line-wire, and theopposite plates being connected by a loop Z as shown. The two loops Zand Z are connected by a third loop Z at either end, and in this thirdloop Z at either end is placed a third telephone apparatus T In theoperation the telephones T T are in the metallic circuit A, as shown.The condenser-plates connected to this circuit, it is seen,can have noeffect upon it. The same is true of telephones T T and their metalliccircuit A and the condenser-plates contained therein. T and T are in ametallic circuit, one limb of which consists of a part of loop Z loop Z,and condensers O C at one end of circuit A, wires 1 and 2 in saidcircuit, and condensers 0 C loop Z, and a part of loop Z at the otherend of the same circuit, while the other limb'in like manner consists ofthe remaining parts of loop Z at either end, loop Z Z condensers 0 0 0 Cand wires 3 and 4. In using either telephone apparatus T what is said atT at either endvcannot be heard at either T, because the disturbance ofthe current at either T cifects equally the two wires 1 and 2, in whichthe T telephonecurrent is moving in opposite directions, and the same istrue for like reasons of the telephones T but what is said at either Tcan be heard at the other T, since the wires 1 and 2 are in eifect but asingle conductor or wire in continuation of loop Z for one side or limbof a new or additional metallic circuit, while wires 3 and 4 make theother limb. No harm is done to the circuit 1 2, because the plates ofthe condensers actually in contact with the lines oilt'er no resistance.The telephones at T work better than those at T and T because they arein a circuit of greater conductivity.

In the diagram at Fig. 2 the two circuits 1 2 and 3 4 end, respectively,in two-contact plug-holes h 71/2, and into which the two telephones Tand T' may be plugged, as indicated, to complete the circuits, while I)b are a pair of idle wires or bars meeting at one end in a similartwo-contact plug-hole 71 into which telephone T may be plugged, andtheir other ends terminating in similar contact plugholes 6' 2, intowhich may be plugged, as shown, wires w and 10 leading from loops Z Zformed as shown in Fig. 1. In this case the loop corresponding to loop Zof Fig. 1 consists of wire w, bar b telephone T bar b, and wire 10*.

In the diagram shown at Fig. 3 the linewires 1 and 2 belong to originalmetallic circuit A, line-wires 3 and l to original metallic circuit A",line-Wires 5 and 6 to original metallic circuit A, and line-wires 7 and8 to original metallic circuit A and each pair of line-wires terminatesin a double contact plug-hole h 7L2 7r h, as shown. Each linewire has acondenser O C &c., and the pairs of condensers in each metallic circuitare looped together by loops Z Z Z Z".

B 13 B are three pairs of idle wires or bars, made up, as shown, of idlebars 1), b b b b and Z), the said pairs terminating at 6 5 one end, asshown, in double-contact plug holes 7r h 71. and the single barsterminating at their other ends in single-contact plugholcs e e e e e e.The idle bars 1), b b and b are furnished, as shown, with con- 7:densers C, C O, and C and the outer plates of these condensers arecoupled in pairs, as shown, by loops Z and Z, which two loops arethemselves looped by means of wires 20' and w and to apair of idle bars13''. Further explanat-ion of Fi 3 is unnecessary.

It will readily be seen that original circuits A and A are loopedtogether for an imposed circuit, that circuits A and A are loopedtogether for a second imposed circuit, and that So the two said imposedcircuits are looped together for a third imposed circuit.

In the arrangement shown in Fig. -.t each. original metallic circuit A AA will be provided with its own telephones, and the eir- S5 cuits A A bymeans of their condensers and the pair of idle bars B, looped as shown,will furnish an additional circuit for a telephone plugged into the idlebars B. A fifth circuit may, as, shown, be imposed upon the threeoriginal circuits A A A, and the fourth already imposed by means of asecond pair of. idle-bars 13 and the two pairs of condensers placed incircuit A and the first pair of idlebars B, and it follows that afteradditional circuits have been imposed upon any number of originalmetallic circuits two metallic cir cuits may always be added to thesystem by the addition of two through-line wires.

The combination, witlrtwo metallic eircui ts, of two pairs ofcondensers, one pair for each circuit, and one plate of a separatecondenser being in contact with each line-wire, while the opposite orfree plates of the pair of con- 105 densers of each circuitare connectedby a metallic loop, and the two loops thus formed are connected by athird, substantially as described.

In testimony whereof I have signed my I10 name to this specification, inthe presence of two subscribing witnesses, this 26th day of February,l891.

IVILLIAM \V. JACQUES.

Witnesses:

Gno. W LLIS PIERCE, FRANK O. Lockwoon.

